Truing device



May 25,y i926., E,585,705

,a M. w. HANsoN TRUI'NG DEVICE Original Filed N'ov. 1, 1919 Sheets-Sheet 1 IH minimum :ummm- "Il My 25 9 11926., LS'

B. M. W. HANSCN TRUING DEVICE Original Filed Nov. l, 1919 2 Sheets-Sheet 2 Fatented May 25, 1926..

l ST

PATENT oFFicE.

BENGT M. W. HANSON, DECEASED, OF HARTFORD, CONNECTICUT; EINAR A. HANSON AND CLARENCE E. WHITNEY EXECUTORS F SAID BENGT M. W. IEANSON, DE-

citasnn.

TRUING DEVICE.

@riginal application nled November 1, 1919, Serial No. 334,952. Divided and this application med J'une 23, 1920. Serial No. 391,013.

This application is a division of my original application Serial No. 334,952, filed November 1st,1919, for metal Working machines.

The present invention relates to a device i or reshaping or re-sharpening a tool. The embodiment of the invention herein selected tor purpose of illustration Will be described with reference to its use for truing a grindl@ ing Wheel employed in the final iinishing operation on a thread and to which use the present device is peculiarly adapted, but" it 1s to be understood that the present disclo-4 sure is by Way oi exempliiication only and l5 the invention is not limited to this particular use and the device is susceptible of other embodiments than that herein sho'vvn.

rll`he object of the invention is to provide a truing device for efficiently generating on a 21@ tool a cutting edge which accurately conforms in shape and size to the cut to be taken in the Work, in the present instance this cut being a thread. Y

ln the accompanying drawings:

Fig. 1 is an assembly view of the truing device and grinding Wheel, the truing device being inside elevation. l

Fi I 2 is an elevational vievi7 looking at the rlght end of Fig. 1.

Fig. 3 is a top plan view of the truing device.

Fig. l is a sectional 'view taken centrally and vertically through the truing device.

Fig. v5 is a sectional view taken on liney 5 5 of Fig. 3.

Fig. 6 is .a front view of the truing device with parts thereoi1 in section.

Referring now to Figs. 1 and 2, the general arrangement ot the truing device and grinding Wheel and the mountings therefor may be readily seen. a denotes a pedestal or tired bed on which is mounted a slide carrying a journal box c supporting the tool Z h'erein shown as a grindingWheel."v e denotes generally the truing deviceinounted on a bracket f Which is adjustably mounted in a "IT-slot 10 of the base a and is provided lwith means for securely locking it in position.

' The constuction of the truing devicewill ,ing wheel and for the irst -be described and then its relation to the grinding Wheel will be pointed out.

Referring particularly to Figs. 3 to 6 inelusive, 11 is an indexible carriage mounted on top ot the bracket 12 is the sharpening tool, for instance, a diamond point which is adapted to be reciprocated by oscillating the hand Wheel 13, and 14 indicates generally a ,gauge for correctly setting the diamond point. The indexible carriage 11 is pivoted one. vertical pin 16 upstanding from the bracket and this carriage moves in a vertical plane over a segmental plate 17 iXed to the top of the bracket i. 18 is a horizontal vshaft journalled in the carriage With its axis at right angles to that of the vertical pin 16, in other Words, the vertical plane which includes the axis of the shaft 18 also includes the axis lof the pin 16. Mounted on the "orvvard end of the shaft 13 is an arm 19 Within which is positioned, subject to longitudinal adjustment on a line parallel to the axis of the shaft 18, the diamond point 12 which is Well adapted tor resurfacing such a tool as herein shown, namely the grinding Wheel d. lin certain of the appended claims, this arm 19 is referred to, ior'convenience, as a tool carrying part. 0n the shaft 18 is a Worm Wheel 21 with which meshesa Worm 22 on the shaft 23 mounted in the carriage and carrying the hand Wheel 13. lt will be noted that the gearing is enclosed Within the carriage Yso that grit and the like cannot gain access thereto and interfere with the accurac extent of rotation of t e hand Wheel 13 is limited by means ot' a fixed pin 25 extending into a notch 26 in the periphery of the Worm Wheel 21. Upon turning the hand Wheel in opposite directions, the shaft 18 isturned and the diamond point will be os-l cillated back and forth across a face or edge of the grinding Wheel which is being resurfaced. The Whole carriage may be swung of the device. rllhe about the pivotal pin 16 in order to bring the diamond point into voperative relation with any one of the faces of the rindpurpose ot in exing it to the proper positlon and holdin it;

there, the segmental plate 17 is notche iti at :28 to receive a spring pressed plunger 29 carried by the carriage. rthe plunger may be withdrawn from the notches by an operating handle handle 30 fixed to a rod 31 having o n its lower end a finger 32 engageable with a pin 33 carried by the plunger. rlt`he position of the notches 28 will, of course, vary in accordance with the angle of the thread to be eut. If a United States standard thread is being cut, in which instance the faces of the thread are at an angle of 60 and the thread is truncated, the notches 28 will be three in number and spaced 60 apart. Of course, the segmental plate can. have two or more series of corresponding notches to make it usable in connection with threads of various types or sizes. When the parts are in the full line position shown in Fig. 3, the diamond point will operate upon the truncated part of the wheel and when in the dotted line position, the diamond point is in position to resurface one side face of the wheel. To resurface the other1 side face, the carriage will be thrown to its extreme opposite position.

lt is, of course, understood that during the final resurfacing operation the grinding wheel has a fixed relation to the center about which the diamond point is indexed. ln the present instance, the center about which the resurfacing tool is indexed lies in a plane passing through the center of the edge of the grinding wheel. It is evident that because of the roughness of the grinding wheel and extremely fine adjustments to give the grindn ing edge thereof the precise shape of the thread, it is practically'impossible to properly true the wheel by using a separate resurfacing tool for each surface thereof or employing a single resurfacing tool requiring a separate setting for each face. Certainly, such adjustments would require the greatest care and patience on the part of the operator-and necessitate a great w'astebf time without any assurance that the grinding wheel as resurfaced was absolutely true. This is particularly the case when a truncated thread is to be,ground for the fiat of the thread has a definite relation to the pitch,

under the United States standard it being one-eighth of the pitch, and itis obvious that after the two side faces of the grinding wheel are resurfaced, there would be the greatest'difticulty in then so adjusting the`V resurfacing tool that the fiat would be the precise size required.

With the device herein described, the objection to the arrangements just noted are entirely eliminated for, as the diamond point is inflexible about a 'fixed axis, a single diamond point may be used and a single setting, which may be obtained with the gauge hereinafter described, is necessary to resurface both faces of the grinding wheel where a V-shaped thread is cut, and all three faces weaver@ of the wheel where a truncated thread is to be ground, with the assurance that in the latter case the fiat will have the proper size in relation to the pitch of the thread. lt will be evident that the 'angular disposition of the side faces of the grinding wheel will accord with the angular disposition of the thread which is being cut, depending upon what type of thread it is. If it is a United States standard, the side Walls of the thread are at an angle of 60.O and consequently the side cutting faces of the wheel will be disposed at an angle of 60O to one another, for the reason that the carriage is so indexed and furthermore this angle will, at all times, and no matter to what extent the wall is resurfaced or resharpened, be bisected by the center line of the grinding wheel. vWhen the diamond point-is indexed to mid-position for resurfacing the flat or truncated part of the wheel, and because of the fixed relation of the wheel to the center about which the carriage is indexed and the fixed relation of the diamond point to that center, the extent of truncation will be correct.

For the purpose of making certain that the extent of the fiat of the wheel shall be correct for any given pitch of thread, the gauge 14 is provided for setting the diamond point so far as its longitudinal adjustment in the arm 19 is concerned. This gauge comprises an arm 35 pivoted on the arm 19 so as to be thrown over in front of the diamond point as indicated in dotted' lines Fig. 4. The end of this pivoted member is threaded to receive gauge plugs 36. A gauge plug will be provided to correspond to the various thread pitches. It will be seen that the gauge arm 35 has a fixed or definite relation to the tool carrying member or arm 19 in that it is pivoted for swinging movement only thereon, and as the arm 19 is fixed against longitudinal movement on the shaft 18, ithas a definite relation to the axis about which the carriage is indexed. It, therefore, follows that by screwing home a gauge plug of proper length into the gauge arm` and then bringing the diamond point into engagement with the end of this plug, the diamond point must be properly adjusted relative to the fixed axis about which it is indexed. That gauge plug is selected which corresponds to the pitch of the thread which is being operated upon, it is screwed home into the arm 35, thrown down in front of the diamond point, and the diamond point is moved through the arm 19 until it reaches the end of this plug when it is clamped into position. The gauge is then thrown back out 0f position as shown in full linesv Fig. 4. By'indexing the carriage, the active facesv of the wheel are roughed out to substantially final form, the wheel being fed up to the diamond point for this purpose and then fastened in position so that its relalll Lasagne tion to the indexible carriage is fixed. rlhen by making a final cut on all three faces of the Wheel, the side faces will be properly shaped and properly sized and at the proper angular' relation with respect t-o one another and the fiat will be accurately inishedto correspond in extent to precisely What it should be for the pitch of the thread being cut.

llt is, of course, well understood that it is necessary to angularly adjust the grinding Wheel in accordance with the lead of the thread to be ground. 'lo accomplish this, ll have shown, for illustrative purposes, the journal box c in which the' shaft on which. the grinding Wheel d is mounted, as being movable in a way 45, the center of curvature of which is the center of the Wheel d by which is meant a point at the axis of the wheel which is included in a plane bisecting the angle of the cutting edge of the Wheel. rll`he line on which the Wheel may be angularly adjusted is indicated by a-a, Fig. l., and this line intersects the axis of the Work. 'llhe work is shown in dotted lines, lFig. l,

and is designated by the letter w. rlhe j our' nal box is locked in adjusted position by means of bolts 46, the heads of which Work in undercut grooves 47. 'llo properly shape the edge of the grinding Wheel so that it will correspond to the shape of the tooth to` be out, it is necessary that the resurfacing or reshaping operation be carried out on a line lying in a plane vvhichincludes the axis of the Work and the line about Which the wheel is angularly adjustable, this latter line, as stated, being the line a-a of Fig. l.. lin the present instance, the diamond point is diametrically opposite to the point of contact between the Work and the tool, and when the diamond point is indexed, and also When it is reciprocated for resurfacing, itmoves substantiallyy in a plane Which includes the line --a and the axis of the Work. llt is obvious that the grinding faces of the Wheel have a line contact With the corresponding faces of the thready operated upon and the plane in which this line of contact lies 'is the plane in which the diamond point is indexed. rlihus it Will be seen that the angular adjustmentof the grinding Wheel is not disturbed in any particular during the resurfacing operation. As the diamond point oscillates about the axis of the shaft 18, it moves slightly out of the horizontal plane but for practical purposes the arc of movement is so small as to be negligible. l

The ways for the slide I) carrying the grinding wheel d, are so arranged that the Wheel, when brought up to the diamond point, moves in the plane in which it rotates, that is, it moves on the line a-a. The bracket f upon which the truing device is carried, though adjustable, is, for practical purposes, fixed to the pedestal a of the machine.

'llhus the alinement of the truingr device and the Wheel is never changed and Y each indexed position back and forth substantially in a plane substantially parallel to that in `which said carriage is indexed.

2. lin combination with a rota-table grinding Wheel, a truing device having a single resurfacing tool, means for positioning and holding said truing tool in contact with the peripheral face of said Wheel and in contact with each side face thereof, and means for moving said tool back and forth when in contact with each face and While said truing tool is held in position by said first mentioned means.

3. A truing device including a resurfacing tool, means for holding the same in a plurality of positions relative to a normally fixed center, said tool being adjustable'on a yline passing substantially through said center, and means for moving said tool bach and forth in each indexed position on a line which extends generally in the same direction as the plane in which the tool is indexed.

4. A. truirngA device including a pivoted carriage' indexible about a normally fixed axis, a shaft mounted on said carriage and arranged at substantially right angles to the axis about Which said carriage is indexed, an arm fixed on said shaft, and a resurfacing tool on said arm longitudinally adjustable on a line generally parallel to the axis of said shaft.

t 5. A resurfacing tool including a pivoted carriage, indexible about a fixed axis, means for holding same in each indexed position., a shaft mounted on said carriage and ar ranged at right angles to the axis on which said carriage is pivoted, a resurfacing tool fixedly mounted on said shaft, and means for turning said shaft in kopposite directions to repeatedly move said resurfacing tool back and forth ineach indexed position. 6. A truing deviceincluding a pivoted lll@ liti@ lili.)

lil@

litt) carriage, a shaft on said carriage, an arm on .nd forth in each indexed osition substantially in a plane substantially parallel to that in which the tool is indexed, and a grinding wheel adjustable to and from said tool on a line passing angularly through said fixed center and substantially lying in a plane in which said tool is indexed.

8. n combination, a grinding wheel having angular adjustment about a diametrical line passing through its center and included in a plane bisecting the angle of the cuttting edge of said grinding Wheel, and a truing device including a resurfacing tool indexible in a plane substantially parallel to said diametrical line and about an axis intersecting said line. y

9. ln combination, a grinding Wheel mo-vable on and angularly adjustable about a diametrical line passing through its center and included in a plane bisecting the angle of the cutting edge of said grinding Wheel, and a truing device including a resurfacing tool indexible in a plane substantially parallel to said diametrical line and about an axis intersecting said line.

. 10. fn combination with a. rotatable grinding wheel having beveled faces and a fla-t peripheral face therebetween, a truing device indexible about a fixed axis, means for holding said truing device in cont-act with and at right angles to each of said faces, and means for moving said truing device back and forth in each indexed position.

11. ln combination, a grinding wheel having bevelled faces and a flatv peripheral face therebetween, a truing device including a carriage indexible about a fixed axis, a resurfacing tool mounted on Saidcarriage, means for indexing said carriage with said tool in Contact with each of said faces, said tool being carried by said carriage for movement on lines which extend substantially in the same direction as the plane in which the tool is indexed, and means for moving said tool back and forth on said lines in each indexed position.

12. In combination, a grinding wheel having bevelled faces and a fiat peripheral face therebetween, a. truing device including a carriage indexible about a fixed axis, a resurfacing tool mounted on said carriage,

means for indexing said carriage with said tool in contact with each of said faces, said tool being carried by said carriage for movement on lines which extend sub-stantially in the same direction as the plane in which the tool is indexed, means for moving Said tool back and forth on said lines in each indexed position, said tool being adjustable to and from said axis, and means for determining the extent of adjustment of said tool.

13. A device .for resurfacing or Vtruing the surfaces of a grinding Wheel and including a resurfacing tool indexible into three posi- Leser/o tions to bring it into proper operative relation to the respective side and peripheral faces of the grinding wheel while maintainingv a single setting of the tool, and means for moving the tool back and forth in each indexed position while maintaining the setting of the tool. l 14. A device for resurfacing or truing the surfaces of a grinding wheel and including va resurfacing tool indexible about a fixed axis to two extreme positions and a midposition to bring it into proper operative relation to the respective surfaces of the grinding wheel, means for holding said tool in its respective indexed positions, and means for moving said tool back and forth in each indexed position, said tool being adjustable relative to said fixed axis and said tool being indexiblev to its respective positions without disturbing the adjustment of the tool relative to the said fixed center.

15. A device for resurfacing or truing the surfaces of a grinding wheel and including a resurfacing tool indexible into more than two positions about a fixed axis, and means for moving the tool back and forth in each indexed position while maintaining the setting of the tool.

16. A device for truing the faces of a. grinding wheel and including a carriage indexible to more than two positions about a fixed axis, means for holding said carriage in each of its indexed positions, a resurfacing tool mounted on said carriage for adjustment relative to said fixed axis, said tool being carried by said carriage for movement on lines which extend substantially in the same direction as the plane in which the tool is indexed` and means for moving said tool back and forth in each indexed posiltion`l 17. lin combination, a truing device including a resurfacing tool indexible into more than two positions about a fixed axis, and means for moving the tool back and forth in each indexedposition While maintaining the setting of the tool; and a grinding Wheel adjustable to and from said tool on a line passing angularly through said fixed center and substantially lying in the plane in which said tool is indexed.

18. In combination, a grinding wheel having angular adjustment about a diametrical line passing through its center and included in a plane bisecting the angle of the cutting edge of said wheel, and a truing device including a resurfacing tool indexible lto more than two positions about a fixed axis intersecting said line, said tool being indexible in a plane substantially parallel to said diametrical line, means for holding said tool in each of its indexed positions, and means for moving said tool back and forth in each of its indexed positions.

19. In combination, a grinding wheel having angular adjustment about a diametrical line passing through its center and included in a plane bisecting the'angle of the cutting edge of said-Wheel, a truing device including a resurfacing tool indexible .to more than two positions about a fixed axis intersecting said line, said tool being indexible in a plane substantially parallel to said diametrical line, means for holding said tool in each of its indexed positions, 10 means for moving said tool back and forth in each of its indexed positions, and means for adjusting said grinding Wheel to and from said tool on said diametrical line.

BENGT M. W. HANSON. 

